Filtration system



May 31, 1927.

H. W'. BLAISDELL FILTRATION SYSTEM Filed April 27. 1922 consists oisuchVminute particles 4asito-have `p The 'il-tered water, upon the quickclos-ing caused, by mo offvalve 24 at Figure 2, is mentum, to rise linsaid stand-pipe 23; the

outlet overflow valve 17 andintake 21 being closedat Vabout this time.As soon as the water has reached a maximum height iii the stand-pipe 23,itwill beginto descend in said `stand-pipe andto rise through Vthe bed11, thus breaking up or disturbing the vrequires not clogging Anature ofthe ilm.- This process rmore than a -Ltew minutes, Vwhereupon the .bedis again ready to filter,

'and :the outlet valve 24 may be reopened.

of the apparatus. back into Aand renovating the filter.- bed. f No waterneeds to be 'wastechand Ithe' As soo-n as the water descends to af:normal level',- seen laty Figure *2, the Voverflow valve f '21V-'7*,m'ayibe opened `and fvalvef21-or `raw water. y y

the nature of a throttle or dis-k pivo'ted at 25 nearoneedgeand having:a handle 26 by which the lvalve may be' swung VVup from lwater upon:the partly closed drive itvto its fully closed posithe deliveryo'f'water is sudsaid 'stand-pipe and increases .the efficiency inimmediately lowing vv"time occupied'for .renovation isvfextremely "fbrieIt isV seen'thatthe bed yis 'renovated by the water after it haslpassedpdown throughfthe bed and Vbecome filtered: thereand thatftherenovating apparatus-fis therefore self-contained and not .dependent-upon 3 other water. supplies.

rllhe'topmostlayer of superneisand 12 7 fthe characteristic ofstrainingI outthebacteria g andfother foreignelements without-the neces-4 vsity of delayingffor 'the ilm -to formagain.

.Thismakesit feasible to Aeect a substantial "reduction in the areailiaryfiiltrationsplants.

through the 'iiiltration lbasin x idly than `is 'the usualpractice;

Elayer *12' may `tbe .'sofiine fas-.to present the Vater may be passedThe A sandcharacteristic of liiot 'being penetrated by the mudwhichyaccumulates reverse-flow operations,

may eventually be removed by a ,sand-wash# lalsoy the usual intakeimprovements {ina-y The .effect of the.

and Y -up through .water moving ldown ytlirou'rh the sand ito -risein-.a standpipe or air vchambeito Y cally-.tdreact and bed and upthrought the saine, y Vfor jthe ""pure of the main .and .aux-

much finore rapy' at tliebottoni of v the body of raw water.` This mudalso may be freed by the' describedrenovating upilow or` reversefflowoperation, but this operation VThe foreign matter which rremains in thebasin docs not impair the eiiiciencyofhc filter, but,-afl'fter manyofthe herein-described such foreign' matter n Vhe reverse-flow operation,it will be understood, may be repeated as'often as necessary tions; anditsrenovating `actiontends to get the ing condition, so thattheintervals of use ing machine.

of the sand-washing .machine may begreatly prolonged. A. y .V .p I.

VVariations may v ,be resorted to within the scope of the invention,land portions of .the be used withou't others VHaving thus describedinvention, claim: Y Y f 1. The process of renovating.afliltration bed,coinprisingshutting oiltheoiitflowpf .water,'permitting said outflowingwater to accumulate between V.the shutting-oft point,` sothat the(accumulation of surplus water' automatically [fiows'back Vthe bed forYthepiirpose specified, i Y

`of raw water, vpermitting,the level of water i kdoes'not remove thevmud romtlie basin.

Vfbetween sand-washing operav filter bedinto better and betterwork-.filter bed .and fthe.

` 2. :The process of lrenovating .a sand iltra- .tion.bed,compri-singshuttingiloiithe supply in thebasin .to belowered beyondthe:.over- Y flow point, shutting? ofi" the .discharge of water fromf.the.basin, and .permittingg-fthe'.V

bed

compress the'. airftliereiikand then automati-l eiect a baclrtlow intothe ose set -forth.y f v .n n l y 3. `That improved process .ofA v.cleaning nloutiiow ott Awater from 'the basin, suddenly stopping saidoutflow bywclosings a valvev7 resulting in an 'accumulation ofv waterbe'- tween the valve .and lbasin, and .wliichproyterfbeds which consistsin,'.p.eri'nitting the duces Aa yhead of water 7.betweensaid ,valve Aand basinjliaving an overbalanced .value or weight sufficient toflowybachvv -up .through the sand bed.

- LHinAM- gw." BLMSDELL. n

